Old radiator vents

dabrakeman

Just trying to see if anybody has any insight into potential venting rates of a couple old radiator vents. They appear to be working (for the most part) but on this system which uses 30 vents I could change them all out but I'd rather not unless necessary. It is easier to do the balancing process with known vent rates but hate throwing something out those working that may have worked for 5 or 10 decades because it's likelihood of failing tomorrow it might be less than a new vent.

One is best I can tell a Dole 933. No I don't think that is a 1933 as you can tell from the picture that I took. It seems to me to be a fairly slow vent. There is probably a dozen of these. The second vent I cannot find any lettering on however if you unscrew the top the mechanism is not two different from a modern Hoffman 1A with a hole that is progressively closed with a cam-shaped shield.

Obviously I can just replace them all or screw around with the settings on the adjustables but there are a lot of radiators and vents so having an idea of what they're venting scale was would have been ideal. Not surprised if it doesn't exist. I did not see the Dole 933

on the Gerry Gill lists but if I had to guess I could believe it is pretty similar to the listed 1933.venting values.

The other seems to vent fairly fast at all settings but hard to say yet since the main venting is still not adequate on the system.

Jamie Hall

Get the main venting right first. Then decide if you have to replace any vents… remember, if it ain't broke, don't fix it.

Long Beach Ed

If you are renovating a steam heating system, all the radiator vents work best when of the same style and manufacturer. They are engineered components,and they work together. They have different closure rates, different temperature behavior characteristics. Some types open faster than others.

If you don't want to spend the money, or you're just a hack, you can mess with 80 year old vents mixed with new vents with a few Chinese two year old vents thrown in. Of course if you just plain like the old stuff, and have the time and patience, keep them and mess around with trying to get them all to play well together.

If you're cleaning up a mess, it's usually best to replace them all.

As Jamie implies, you do open a can of worms once you start playing with the venting.

Mad Dog_2

Gortons or Hoffmans..Mad Dog

Steamhead

The adjustable one is a Dole #1A, whose venting rates are similar to the Hoffman #1A.

I've never seen a Dole #933, but it looks similar to the #1933.

@Jamie Hall is right- get your main vents right first.